Ímar (; died c. 873) was a Viking leader in Ireland and Scotland in the mid-late ninth century who founded the Uí Ímair dynasty, and whose descendants would go on to dominate the Irish Sea region for several centuries. He was the son of the king of Lochlann, identified in the non-contemporary Fragmentary Annals of Ireland as Gofraid. The Fragmentary Annals name Auisle and Amlaíb Conung as his brothers. Another Viking leader, Halfdan Ragnarsson, is considered by some scholars to be another brother. The Irish Annals title Amlaíb, Ímar and Auisle "kings of the foreigners". Modern scholars use the title " kings of Dublin" after the Viking settlement which formed the base of their power. Some scholars consider Ímar to be identical to Ivar the Boneless, a Viking commander of the Great Heathen Army named in contemporary English sources who also appears in the Icelandic sagas as a son of the legendary Viking Ragnar Lodbrok.
During the late 850s and early 860s Ímar was involved in a protracted conflict with Máel Sechnaill, overking of the Southern Uí Néill and the most powerful ruler in Ireland. The cause of the conflict is uncertain, but it may have been sparked by competition for control of Munster and its resources. Ímar allied successively with Cerball, King of Ossory and Áed Findliath, overking of the Northern Uí Néill against Máel Sechnaill. Máel Sechnaill died in 862 and his lands were split, effectively ending the conflict. Following this Ímar and his kin warred with several Irish leaders in an attempt to expand their kingdom's influence. Ímar disappears from the historical record in Ireland between the years 864 and 870; this is consistent with Ímar being identical to Ivar the Boneless - Ivar was active in England between these two dates and he is not mentioned by English sources after 870. In 870 the annals record that Dumbarton Rock, the chief fortress of the Kingdom of Strathclyde, was successfully captured by Ímar and Amlaíb following a four month long siege.
Ímar died in 873 and is given the title "King of the Norsemen of all Ireland and Britain" in contemporary annals. The Fragmentary Annals record that Ímar's father also died that year, and it is believed that at that time their combined territory encompassed Dublin, the Isle of Man, the Western Isles, Orkney, and large parts of the northern and western Scottish coast including Argyll, Caithness and Sutherland.
Imar or IMAR may refer to:
- Emar, an ancient Amorite city located in modern-day Syria
- Ímar, a 9th-century Norse king
- Ímar of Limerick, Viking ruler
- Imar the Servitor, 1914 American film
- Inner Mongolia Autonomous Region of China